What is the normal function of the SLC19A3 gene?

The SLC19A3 gene provides instructions for making a protein called a thiamine transporter, which moves a vitamin called thiamine into cells. Thiamine, also known as vitamin B1, is obtained from the diet. It is involved in many cellular processes, and is necessary for proper functioning of the nervous system. Molecules made from thiamine are important in the breakdown of sugars and protein building blocks (amino acids). Thiamine is also involved in the production of certain chemicals that relay signals in the nervous system (neurotransmitters).

Does the SLC19A3 gene share characteristics with other genes?

The SLC19A3 gene belongs to a family of genes called SLC (solute carriers).

A gene family is a group of genes that share important characteristics. Classifying individual genes into families helps researchers describe how genes are related to each other. For more information, see What are gene families? in the Handbook.

How are changes in the SLC19A3 gene related to health conditions?

At least seven mutations in the SLC19A3 gene have been identified in people with biotin-thiamine-responsive basal ganglia disease, a disorder that involves recurrent episodes of brain dysfunction (encephalopathy) and a variety of neurological problems that gradually get worse. SLC19A3 gene mutations likely result in a protein with impaired ability to transport thiamine into cells, resulting in decreased absorption of the vitamin and leading to neurological dysfunction. Using medical imaging, abnormalities can be seen in several parts of the brain, including a group of structures called the basal ganglia, which help control movement, but the relationship between these specific brain abnormalities and the abnormal thiamine transporter is unknown.

other disorders - caused by mutations in the SLC19A3 gene

SLC19A3 gene mutations have also been identified in individuals with other neurological disorders whose signs and symptoms overlap those of biotin-thiamine-responsive basal ganglia disease (described above). These include a disorder called early infantile lethal encephalopathy and another disorder that begins in early infancy and causes seizures and brain deterioration (atrophy). A small number of individuals with signs and symptoms similar to those of the neurological disorders Leigh syndrome and Wernicke encephalopathy have also been found to have SLC19A3 gene mutations. It is unclear why mutations in this gene cause varying signs and symptoms in different individuals.

The resources on this site should not be used as a substitute for
professional medical care or advice. Users seeking information about
a personal genetic disease, syndrome, or condition should consult with a qualified
healthcare professional.
See How can I find a genetics professional in my area? in the Handbook.